1. Field of the Invention
This invention relates generally to sliding doors and more particularly to a novel bottom guide roller assembly for such sliding doors.
2. Prior Art
At the outset, it is important to note that the guide roller assembly of this invention may be utilized on a variety of sliding doors and other sliding closures which are collectively referred to herein simply as sliding doors. The invention, however, is intended primarily for use on sliding glass doors of the type used as patio doors in private dwellings and the like. For this reason, the invention will be described in the context of such sliding glass doors.
Sliding glass doors of the kind referred to are well known and comprise a rectangular metal frame to be fixed within a door opening in a wall and at least a pair of relatively movable door panels mounted within the frame. One of these panels is generally a fixed panel which is securely fastened to the frame and occupies only a portion of the frame opening so that the remainder of the frame opening provides an access opening through the frame. The other panel of the door assembly is a movable panel which is supported within the frame for edgewise sliding movement to and from a closed position wherein the panel closes the access opening. In its open position, the movable panel overlaps the stationary panel and uncovers the access opening for free passage of persons therethrough.
The movable door panel is supported at its bottom on a track extending along the bottom of the door frame by means of roller assemblies mounted within a downwardly opening channel along the lower edge of the door panel. Each roller assembly has a peripherally grooved roller which rides in the track and is supported for vertical floating movement on a mounting bracket which is fixed within the bottom door channel. The roller carrier is spring loaded downwardly toward the track so as to yieldably retain the roller in proper guiding contact with the track in the event that the sliding door panel is inadvertently elevated away from the track during opening and closing movement thereof.
A vast assortment of such sliding door roller assemblies have been devised. One such roller assembly is described in my prior U.S. Pat. No. 3,879,893. Other roller assemblies are described in U.S. Pat. Nos. 3,090,084, 3,698,036, and 3,722,028.
Sliding door supporting roller assemblies of the character described requires some means of transferring the weight of the sliding door to the assembly rollers. This is generally accomplished by some type of a limit stop arrangement operative between the guide roller carrier and the roller mounting bracket. In my prior U.S. Pat. No. 3,879,893, for example, the limit stop is a vertical plunger which is slidable in the guide roller mounting bracket and surrounded by a spring for urging the plunger downwardly toward the roller carrier. Threaded in the mounting bracket is a set screw which is accessible through an opening in the side of the sliding door, whereby the screw may be tightened to clamp the limit stop plunger in fixed position relative to the mounting bracket. The roller assembly, when installed on a sliding door, is set by elevating the door to raise its bottom edge out of contact with the bottom of the door frame, then releasing the limit stop screws to permit downward spring projection of the limit stops into contact with the guide roller carriers, and finally tightening the screws to lock the limit stops in fixed position. When the sliding door is then released, the weight of the door is transmitted through the limit stop, the guide roller carriers, and the guide rollers to the guide track on the door frame.
This roller assembly of my prior patent is superior to those of the other listed patents for the reason that proper setting or adjustment of my patented roller assemblies may be easily accomplished from the sides of the door. This is due, of course, to the accessibility of the limit stop clamp screws through the side openings in the door. The other patented roller assemblies referred to lack comparable adjustment accessibility and hence are much more difficult to adjust or set.